A model for inheritance and overriding in deductive object-oriented systems (Extended Abstract)

We present a simple model for deductive objectoriented systems with inheritance and overriding. In this model we define a declarative semantics based on preferred minimal models, we present bottom-up and top-down procedures for query evaluation, and we note that these procedures are sound with respect to the declarative semantics. 1 Introduction The object-oriented approach to systems analysis and design, software development, and data modelling has recently attracted considerable interest. Although many object-oriented CASE tools, programming languages, and database systems have been implemented and usefully applied, theoreticians remain concerned that object-oriented systems lack the kind of simple mathematical foundation possessed by functional programming languages or relational database systems. In addition, those object-oriented database systems that have been implemented lack the kind of deductive component that has proved so useful for views in relational database systems and ..